It remains unknown what this beta release for a newer iOS version has to offer, however, the change-log calls it a beta version containing bug fixes and improvements:

“This beta version of iOS 9.3.2 contains bug fixes and improvements”

The mention of iOS 9.3.2 in the changelog of iOS 9.3.3 could be a typo, but it could also mean that it’s an upgrade to current latest iOS 9.3.2 to fix the 9.-7-inch iPad Pro bricking “Error 56”.

After seeing a growing number of bricked devices due to iOS 9.3.2, Apple not only suggested the affected iPad Pro owners to contact Apple Support, the fruit company also pull the software update for the 9.7-inch iPad Pro model.